2.8.10. @ConfigurationProperties vs. @Value
The @Value annotation is a core container feature, and it does not provide the same features as type-safe configuration properties. The following table summarizes the features that are supported by @ConfigurationProperties and @Value:
Feature | @ConfigurationProperties | @Value |
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Relaxed binding | Yes | Limited (see note below) |
Meta-data support | Yes | No |
SpEL evaluation | No | Yes |
If you do want to use @Value, we recommend that you refer to property names using their canonical form (kebab-case using only lowercase letters). This will allow Spring Boot to use the same logic as it does when relaxed binding @ConfigurationProperties. For example, @Value(“{demo.item-price}”) will pick up demo.item-price and demo.itemPrice forms from the application.properties file, as well as DEMO_ITEMPRICE from the system environment. If you used @Value(“{demo.itemPrice}”) instead, demo.item-price and DEMO_ITEMPRICE would not be considered. |
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If you define a set of configuration keys for your own components, we recommend you group them in a POJO annotated with @ConfigurationProperties. Doing so will provide you with structured, type-safe object that you can inject into your own beans.
SpEL expressions from application property files are not processed at time of parsing these files and populating the environment. However, it is possible to write a SpEL expression in @Value. If the value of a property from an application property file is a SpEL expression, it will be evaluated when consumed through @Value.